The "/vdiff" page:

URL: /vdiff?from=TAG&to=TAG
Show the difference between two check-ins identified by the from= and
to= query parameters.
Query parameters:
from=TAG Left side of the comparison
to=TAG Right side of the comparison
branch=TAG Show all changes on a particular branch
v=BOOLEAN Default true. If false, only list files that have changed
sbs=BOOLEAN Side-by-side diff if true. Unified diff if false
glob=STRING only diff files matching this glob
dc=N show N lines of context around each diff
w ignore whitespace when computing diffs
nohdr omit the description at the top of the page
Show all differences between two check-ins.